Functionalized olefin polymers

Field of the invention

This invention relates to a composition comprising a functionalized C3-C40 olefin polymer. This invention further relates to functionalized olefin polymers, as well as processes to produce and use functionalized olefin polymers including applications as adhesives, tie layers, primers, compatibility agents, and the like.

Background of the invention

Olefin based polymers are widely used in various applications due to their being chemically inert, having low density, and low cost. Applications include adhesives, tie layers, films, fibers, and combinations thereof.

Olefin based polymers may be formed into various films, which may be laminated to, coated on, or co-extruded with various substrates. The film and the substrate may be combined with other materials to form a structure having a plurality of layers, each layer having a specific purpose. Packaging laminates, for example, may comprise a plurality of layers, such as a configurationally rigid core layer of paper or paperboard, an outer liquid-tight layer, an oxygen gas barrier such as a mid-layer of aluminum foil, and/or other layers depending on application needs.

To provide effective adhesion, it is important that good bonding strength or intimate integrity between the layers be achieved for most applications. However, relatively non-polar olefin based polymers do not normally adhere well to substrates which are more polar.

In addition, the set time of an adhesive may need to be within limits consistent with a proposed end use. Tailoring of an adhesive set time however may be accomplished at the expense of other attributes of an adhesive. For example, while inclusion of various forms of wax (e.g., polyethylene wax) may reduce a set time of an adhesive, the inclusion of a wax may also reduce or destroy adhesive properties in particular temperature ranges, and/or to particular substrates, especially polar substrates.

Adhesives are typically not heat stable, especially with respect to color over a period of time when the adhesive is heated at or above its melting point. Stability issues related to thermal degradation, including those related to bond strength and color body formation at elevated temperatures, may render various adhesives unfit for a variety of end uses.

There thus remains a need for an adhesive that will intimately bond to both polar and non-polar substrates, preferably one that exhibits a superior durability of bond strength under various temperature conditions at particular set times and in the presence of aggressive products, and that is heat stable at elevated temperatures.

Summary of the invention

This invention relates to a composition comprising a functionalized C3 to C40 olefin polymer comprising at least 50 mol % of one or more C3 to C40 olefins and having: a) a Dot T-Peel of 1 Newton or more on Kraft paper; b) an Mw of 10,000 to 100,000; and c) a branching index (g') of 0.98 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 60,000, or a branching index (g') of 0.95 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 100,000. This invention further relates to such functionalized C3 to C40 olefin polymers blended with other polymers. In a preferred embodiment the functionalized C3 to C40 olefin polymer is blended with the same or different non-functionalized C3 to C40 olefin polymer comprising at least 50 mol % of one or more C3 to C40 olefins and having: a) a Dot T-Peel of 1 Newton or more on Kraft paper; b) an Mw of 10,000 to 100,000; and c) a branching index (g') of 0.98 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 60,000, or a branching index (g') of 0.95 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 100,000.

By "functionalized C3 to C40 olefin polymer" is meant that the C3 to C40 olefin polymer is contacted with a functional group, and optionally a catalyst, heat, initiator, or free radical source to cause all or part of the functional group to incorporate, graft, bond to, physically attach to, and or chemically attach to the C3 to C40 olefin polymer. By "functional group" is meant any compound with a weight average molecular weight of 1000 or less that contains a heteroatom and or an unsaturation. Preferably the functional group is a compound containing a heteroatom, such as maleic anhydride. Preferred functional groups include organic acids, organic amides, organic amines, organic esters, organic anhydrides, organic alcohols, organic acid halides (such as acid chlorides, acid bromides, etc.) organic peroxides, and the like.

For ease of reference the functionalized C3 to C40 olefin polymer may be abbreviated as F-POA and a C3 to C40 olefin polymer that has NOT been functionalized may be referred to as a POA.

Detailed description

For the purposes of this invention and the claims thereto and for ease of reference, when a polymer is referred to as comprising an olefin, the olefin present in the polymer is the polymerized form of the olefin.

In a preferred embodiment, this invention relates to a composition comprising:

1) 0.5 to 99 weight % (preferably 1 to 75 weight %, more preferably 1.5 to 40 weight %, preferably 2 to 20 weight %, preferably 2.5 to 10 weight %) of a functionalized C3 to C40 olefin polymer comprising at least 50 mol % of one or more C3 to C40 olefins and having: a) a Dot T-Peel of 1 Newton or more on Kraft paper; b) an Mw of 10,000 to 100,000; and c) a branching index (g') of 0.98 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 60,000, or a branching index (g') of 0.95 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 100,000.

2) 99 to 1 weight % (preferably 99 to 25 weight %, more preferably 98.5 to 60 weight %, preferably 98 to 80 weight %, preferably 97.5 to 90 weight %) of one or more additional polymers different from the functionalized C3 to C40 olefin polymer,

based upon the weight of the additional polymer(s) and the functionalized C3 to C40 olefin polymer.

In a preferred embodiment the additional polymer comprises one or more C3 to C40 olefin polymer comprising at least 50 mol % of one or more C3 to C40 olefins and having: a) a Dot T-Peel of 1 Newton or more on Kraft paper; b) an Mw of 10,000 to 100,000; and c) a branching index (g') of 0.98 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 60,000, or a branching index (g') of 0.95 or less measured at the Mz of the polymer when the polymer has an Mw of 10,000 to 100,000.

In a preferred embodiment this invention relates to a blend comprising F-POA and between 1 and 90 weight % tackifier, preferably between 5 and 75 weight %, more preferably between 10 and 60 weight %, more preferably between 15 and 50% of tackifier, based upon the weight of the blend, and between 10 and 99 weight % of the F-POA, preferably between 95 and 25 weight %, more preferably between 40 and 90 weight %, more preferably between 85 and 50% of the F-POA.

In another preferred embodiment this invention relates to a blend comprising F-POA, POA and between 1 and 90 weight % tackifier, preferably between 5 and 75 weight %, more preferably between 10 and 60 weight %, more preferably between 15 and 50% of tackifier, based upon the weight of the blend, and between 10 and 99 weight % of F-POA and POA, preferably between 95 and 25 weight %, more preferably between 40 and 90 weight %, more preferably between 85 and 50%.

In a preferred embodiment comprising POA and F-POA, the POA and the F-POA may include the same olefin polymer or blend of olefin polymers which is/are functionalized to become the F-POA, which are then blended with POA. In another embodiment, the olefin polymer or blend of olefin polymers of the POA may be different from the olefin polymer or blend of olefin polymers functionalized to become the F-POA. In still another embodiment, the olefin polymer or blend of olefin polymers of the POA may be the exact same olefin polymer or blend of olefin polymers that has been functionalized to become the F-POA. In yet another embodiment, the F-POA may include functionalized analogs of the exact same olefin polymer or blend of olefin polymers as is in the POA. Preferably, the POA comprises the exact same olefin polymer as the F-POA, which has been functionalized with maleic anhydride.

C3 to C40 Olefin Polymers (POA's)

Preferred C3 to C40 olefin polymers (also called "POA's" or "POA polymers") useful in this invention are those described in U.S. Ser. No. 10/686,951, filed Oct. 15, 2003 and U.S. Ser. No. 10/687,508, filed Oct. 15, 2003, which are incorporated by reference herein. In particular, pages 23 to 91 of U.S. Ser. No. 10/686,951 and pages 22 to 168 of U.S. Ser. No. 10/687,508 provide specific instruction on how to produce the C3 to C40 olefin polymers useful herein. In general preferred POA's comprise a polypropylene prepared utilizing two or more catalysts (typically metallocene catalysts), wherein one catalyst is selected as being capable of producing essentially atactic polypropylene (aPP), and the other metallocene catalyst is selected as being capable of producing isotactic polypropylene (iPP) under the polymerization conditions utilized. Preferably, under the polymerization conditions utilized, incorporation of aPP and iPP polymer chains may occur within the in-reactor blend such that an amount of amorphous polypropylene present in the POA polymer is grafted to isotactic polypropylene, represented herein as (aPP-g-IPP) and/or such that an amount of isotactic polypropylene present in the POA polymer is grafted to amorphous polypropylene, represented herein as (iPP-g-aPP).

Preferred POA's useful in this invention include olefin polymer comprising one or more C.sub.3 to C.sub.40 olefins, preferably propylene, and less than 50 mole % of ethylene, having: a) a Dot T-Peel between 1 Newton and the 10,000 Newtons; and b) a Mz/Mn of 2 to 200; and/or c) an Mw of X and a g' of Y (measured at the Mz of the polymer) according to the following Table 1:

TABLE-US-00001 TABLE 1 X (Mw) Y (g') 100,000 or less, preferably 80,000 or less, preferably 0.9 or less, 70,000 or less, more preferably 60,000 or less, more preferably 0.7 preferably 50,000 or less, more preferably 40,000 or or less; less, more preferably 30,000 or less, more preferably preferably 20,000 or less, more preferably 10,000 or less. between 0.5- In some embodiments X is also at least 7000, more 0.9 preferably 10,000, more preferably at least 15,000. 75,000 or less, preferably 70,000 or less, more preferably 0.92 or less, 60,000 or less, more preferably 50,000 or less, more preferably, 0.6 preferably 40,000 or less, more preferably 30,000 or less, or less; more preferably 20,000 or less, more preferably 10,000 preferably or less. In some embodiments A is also at least 1000, between 0.4- preferably at least 2000, more preferably at least 3000, 0.6- more preferably at least 4000, more preferably at least 5000, more preferably at least 7000, more preferably 10,000, more preferably at least 15,000. 50,000 or less, more preferably 40,000 or less, more 0.95 or less, preferably 30,000 or less, more preferably 20,000 or preferably 0.7 less, more preferably 10,000 or less. In some embodi- or less; ments A is also at least 1000, preferably at least 2000, preferably more preferably at least 3000, more preferably at least between 0.5- 4000, more preferably at least 5000, more preferably at 0.7- least 7000, more preferably 10,000, more preferably at least 15,000. 30,000 or less, preferably 25,000 or less, more preferably 0.98 or less 20,000 or less, more preferably 15,000 or less, more preferably preferably 10,000 or less. In some embodiments A is between 0.7- also at least 1000, preferably at least 2000, more 0.98 preferably at least 3000, more preferably at least 4000, more preferably at least 5000, more preferably at least 7000, more preferably 10,000, more preferably at least 15,000.

Preferred POA's useful in this invention include olefin polymers comprising one or more C.sub.3 to C.sub.40 olefins, preferably propylene, and less than 50 mole % of ethylene, having: a) a Dot T-Peel between 1 Newton and 10,000 Newtons; and b) a Mz/Mn of 2 to 200; and c) an Mw between 15,000 and 100,000; and d) a g'<(10.sup.-12 Mw.sup.2-10.sup.-6 Mw+1.0178).

In an embodiment, the g' may be 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less when measured at the Mz of the polymer.

In another embodiment the POA may have a peak melting point (Tm) between 40 and 250.degree. C., or between 60 and 190.degree. C., or between 60 and 150.degree. C., or between 80 and 130.degree. C. In some embodiments the peak melting point is between 60 and 160.degree. C. In other embodiments the peak melting point is between 124-140.degree. C. In other embodiments, the peak melting temperature is between 40-130.degree. C.

In another embodiment the POA may have a viscosity (also referred to a Brookfield Viscosity or Melt Viscosity) of 90,000 mPasec or less at 190.degree. C. (as measured by ASTM D 3236 at 190.degree. C.); or 80,000 or less, or 70,000 or less, or 60,000 or less, or 50,000 or less, or 40,000 or less, or 30,000 or less, or 20,000 or less, or 10,000 or less, or 8,000 or less, or 5000 or less, or 4000 or less, or 3000 or less, or 1500 or less, or between 250 and 6000 mPasec, or between 500 and 5500 mPasec, or between 500 and 3000 mPasec, or between 500 and 1500 mPasec, and/or a viscosity of 8000 mPasec or less at 160.degree. C. (as measured by ASTM D 3236 at 160.degree. C.); or 7000 or less, or 6000 or less, or 5000 or less, or 4000 or less, or 3000 or less, or 1500 or less, or between 250 and 6000 mPasec, or between 500 and 5500 mPasec, or between 500 and 3000 mPasec, or between 500 and 1500 mPasec. In other embodiments the viscosity is 200,000 mPasec or less at 190.degree. C., depending on the application. In other embodiments the olefin polymer may have a viscosity of about 50,000 mPasec or less, depending on the application.

In another embodiment the POA may also have a heat of fusion of 70 J/g or less, or 60 J/g or less, or 50 J/g or less; or 40 J/g or less, or 30 J/g or less, or 20 J/g or less and greater than zero, or greater than 1 J/g, or greater than 10 J/g, or between 20 and 50 J/g.

In another embodiment the oPOA may also have a Shore A Hardness (as measured by ASTM2240) of 95 or less, 70 or less, or 60 or less, or 50 or less, or 40 or less or 30 or less, or 20 or less. In other embodiments, the Shore A Hardness may be 5 or more, 10 or more, or 15 or more. In certain applications, such as packaging, the Shore A Hardness is preferably about 60-70.

In still another embodiment the POA may have a Mz/Mn of 2 to 200, preferably 2 to 150, preferably 10 to 100.

In another embodiment the POA may have a Shear Adhesion Fail Temperature (SAFT--as measured by ASTM4498) of 200.degree. C. or less, or of 40.degree. C. to 150.degree. C., or 60.degree. C. to 130.degree. C., or 65.degree. C. to 110.degree. C., or 70.degree. C. to 80.degree. C. In certain embodiments SAFT's of 130.degree. C. to 140.degree. C. may be preferred.

In another embodiment the POA may have a Dot T-Peel of between 1 Newton and 10,000 Newtons, or 3 and 4000 Newtons, or between 5 and 3000 Newtons, or between 10 and 2000 Newtons, or between 15 and 1000 Newtons. As used herein, Dot T-Peel is determined according to ASTM D 1876, except that the specimen is produced by combining two 1 inch by 3 inch (2.54 cm.times.7.62 cm) Kraft paper substrate cut outs with a dot of adhesive with a volume that, when compressed under a 500 gram weight occupies about 1 square inch of area (1 inch=2.54 cm). Once made all the specimens are pulled apart in side by side testing (at a rate of 2 inches per minute) by a device which records the destructive force of the insult being applied. The maximum force achieved for each sample tested was recorded and averaged, thus producing the Average Maximum Force which is reported as the Dot T-Peel.

In another embodiment the POA may have a set time of several days to about 0.1 seconds or less, or 60 seconds or less, or 30 seconds or less, or 20 seconds or less, or 15 seconds or less, or 10 seconds or less, or 5 seconds or less, or 4 seconds or less, or 3 seconds or less, or 2 seconds or less, or 1 second or less.

In another embodiment the POA may have a Mw/Mn of 2 to 75, or 4 to 60, or 5 to 50, or 6 to 20.

In yet another embodiment, the POA may have an Mz of 1,000,000 or less, preferably 15,000 to 1,000,000, or 20,000 to 800,000, or 25,000 to 350,000.

In another embodiment the POA may also have a strain at break (as measured by ASTM D-1708 at 25.degree. C.) of 50 to 1000%, preferably 80 to 200%. In some other embodiments the strain at break is 100 to 500%.

In another embodiment, the POA has a tensile strength at break (as measured by ASTM D-1708 at 25.degree. C.) of 0.5 MPa or more, alternatively 0.75 MPa or more, alternatively 1.0 MPa or more, alternatively 1.5 MPa or more, alternatively 2.0 MPa or more, alternatively 2.5 MPa or more, alternatively 3.0 MPa or more, alternatively 3.5 MPa or more.

In another embodiment, the POA also has a crystallization point (Tc) between 20.degree. C. and 110.degree. C. In some embodiments the Tc is between 70.degree. C. to 100.degree. C. In other embodiments the Tc is between 30.degree. C. and 80.degree. C. In other embodiments the Tc is between 20.degree. C. and 50.degree. C.

In some embodiments the POA may have a slope of -0.1 or less, preferably -0.15 or less, more preferably -0.25 or less in the trace of complex viscosity versus temperature as shown in FIG. 1 (as measured by ARES dynamic mechanical spectrometer operating at a frequency of 10 rad/s, with a strain of 20% under a nitrogen atmosphere, and a cooling rate of 10.degree. C./min) over the range of temperatures from Tc+10.degree. C. to Tc+40.degree. C. The slope is defined for use herein as a derivative of log(complex viscosity) with respect to temperature.

In another embodiment the POA has a Tc that is at least 10.degree. C. below the Tm, preferably at least 20.degree. C. below the Tm, preferably at least 30.degree. C. below the Tm, more preferably at least 35.degree. C. below the Tm.

In another embodiment some POA's described above may have a melt index ratio (I.sub.10/I.sub.2) of 6.5 or less, preferably 6.0 or less, preferably 5.5 or less, preferably 5.0 or less, preferably 4.5 or less, preferably between 1 and 6.0. (I.sub.10 and I.sub.2 are measured according to ASTM1238 D, 2.16 kg, 190.degree. C.).

In another embodiment some POA's described above may have a melt index (as determined by ASTM1238 D, 2.16 kg, 190.degree. C.) of 25 dg/min or more, preferably 50 dg/min or more, preferably 100 dg/min or more, more preferably 200 dg/min or more, more preferably 500 dg/mn or more, more preferably 2000 dg/min or more. In another embodiment the POA has a melt index of 900 dg/min or more.

In another embodiment the POA may have a range of crystallization of 10 to 60.degree. C. wide, preferably 20 to 50.degree. C., preferably 30 to 45.degree. C. in the DSC traces. In DSC traces where there are two or more non-overlapping peaks, then each peak has a range of crystallization of 10 to 60.degree. C. wide, preferably 20 to 50.degree. C., preferably 30 to 45.degree. C. in the DSC traces.

In another embodiment the POA may have a molecular weight distribution (Mw/Mn) of at least 2, preferably at least 5, preferably at least 10, even more preferably at least 20.

In another embodiment the POA may have a unimodal, bimodal, or multimodal molecular weight distribution (Mw/Mn) distribution of polymer species as determined by Size Exclusion Chromatography (SEC). By bimodal or multimodal is meant that the SEC trace has more than one peak or inflection points. An inflection point is that point where the second derivative of the curve changes in sign (e.g., from negative to positive or vice versus).

In another embodiment the POA may have an energy of activation of 8 to 15 cal/mol. Energy of activation being calculated using the relationships of complex viscosity and temperature over the region where thermal effects are responsible for viscosity increase (assuming an Arrhenius-like relationship).

In another embodiment the POA's utilized in this invention may have a crystallinity of at least 5%.

In another embodiment the POA's described above may also have one or more of the following: a) a peak melting point between 60 and 190.degree. C., or between about 60 and 150.degree. C., or between 80 and 130.degree. C.; and/or b) a viscosity of 8000 mPasec or less at 190.degree. C. (as measured by ASTM D 3236 at 190.degree. C.); or 5000 or less, or 4000 or less, or 3000 or less, or 1500 or less, or between 250 and 6000 mPasec, or between 500 and 5500 mPasec, or between 500 and 3000 mPasec, or between 500 and 1500 mPasec, or a viscosity of 8000 mPasec or less at 160.degree. C. (as measured by ASTM D 3236 at 160.degree. C.); or 7000 or less, or 6000 or less, or 5000 or less, or 4000 or less, or 3000 or less, or 1500 or less, or between 250 and 6000 mPasec, or between 500 and 5500 mPasec, or between 500 and 3000 mPasec, or between 500 and 1500 mPasec; and/or c) an H.sub.f (Heat of fusion) of 70 J/g or less, or 60 J/g or less, or 50 J/g or less; or 40 J/g or less, or 30 J/g or less, or 20 J/g or less and greater than zero, or greater than 1 J/g, or greater than 10 J/g, or between 20 and 50 J/g; and or d) a Shore A Hardness (as measured by ASTM2240) of 90 or less, or 80 or less, or 70 or less, or 60 or less or 50 or less, or 40 or less; and or e) a Shear Adhesion Fail Temperature (SAFT--as measured by ASTM4498) of 40 to 150.degree. C., or 60 to 130.degree. C., or 65 to 110.degree. C., or 70-80.degree. C.; and or; f) a Dot T-Peel of between 1 Newton and 10,000 Newtons, or 3 and 4000 Newtons, or between 5 and 3000 Newtons, or between 10 and 2000 Newtons, or between 15 and 1000 Newtons; and/or g) a set time of several days to 0.1 second, or 60 seconds or less, or 30 seconds or less, or 20 seconds or less, or 15 seconds or less, or 10 seconds or less, or 5 seconds or less, or 4 seconds or less, or 3 seconds or less, more or 2 seconds or less, or 1 second or less; and or h) an Mw/Mn of greater than 1 to 75, or 2 to 60, or 2 to 50, or 3 to 20; and/or i) an Mz of 1,000,000 or less, preferably 15,000 to 500,000, or 20,000 to 400,000, or 25,000 to 350,000.

Useful combinations of features include POA's having a Dot T-Peel of between 1 Newton and 10,000 Newtons, or 3 and 4000 Newtons, or between 5 and 3000 Newtons, or between 10 and 2000 Newtons, or between 15 and 1000 Newtons and:

1. an Mw of 30,000 or less, a peak melting point between 60 and 190.degree. C., a Heat of fusion of 1 to 70 J/g, a branching index (g') of 0.90 or less measured at the Mz of the polymer; and a melt viscosity of 8000 mPasec or less at 190.degree. C.; or

2. an Mz of 20,000 to 500,000 and a SAFT of 60 to 150.degree. C.; or

3. an Mz/Mn of 2-200 and a set time of 2 seconds or less; or

4. an H.sub.f (heat of fusion) of 20 to 50 J/g, an Mz or 20,000-500,000 and a shore hardness of 50 or less; or

5. an Mw/Mn of greater than 1 to 50, a viscosity of 5000 or less mPasec at 190.degree. C.; or

6. an Mw of 50,000 or less, a peak melting point between 60 and 190.degree. C., a heat of fusion of 2 to 70 J/g, a branching index (g') of 0.70 or less measured at the Mz of the polymer, and a melt viscosity of 8000 mPasec or less at 190.degree. C.

In a preferred embodiment, the POA comprises amorphous, crystalline and branch-block molecular structures.

In a preferred embodiment the POA comprises at least 50 weight % propylene, preferably at least 60% propylene, alternatively at least 70% propylene, alternatively at least 80% propylene. In another embodiment the POA comprises propylene and 15 mole % ethylene or less, preferably 10 mole % ethylene or less, more preferably 9 mole % ethylene or less, more preferably 8 mole % ethylene or less, more preferably 7 mole % ethylene or less, more preferably 6 mole % ethylene or less, more preferably 5 mole % ethylene or less, more preferably 4 mole % ethylene or less, more preferably 3 mole % ethylene or less, more preferably 2 mole % ethylene or less, more preferably 1 mole % ethylene or less.

In another embodiment the POA comprises less than 5 mole % of ethylene, preferably less than 4.5 mole % ethylene, preferably less than 4.0 mole % ethylene, alternatively less than 3.5 mole % ethylene, alternatively less than 3.0 mole % ethylene, alternatively less than 2.5 mole % ethylene, alternatively less than 2.0 mole % ethylene, alternatively less than 1.5 mole % ethylene, alternatively less than 1.0 mole % ethylene, alternatively less than 0.5 mole % ethylene, alternatively less than 0.25 mole % ethylene, alternatively 0 mole % ethylene.

In another embodiment the POA has a glass transition temperature (Tg) as measured by ASTM E 1356 of 5.degree. C. or less, preferably 0.degree. C. or less, preferably -5.degree. C. or less, alternatively between -5.degree. C. and -40.degree. C., alternatively between -5.degree. C. and -15.degree. C.

In another embodiment the POA has an amorphous content of at least 50%, alternatively at least 60%, alternatively at least 70%, even alternatively between 50 and 99%. Percent amorphous content is determined using Differential Scanning calorimetry measurement according to ASTM E 794-85.

In another embodiment the POA has a crystallinity of 40% or less, alternatively 30% or less, alternatively 20% or less, even alternatively between 10% and 30%. Percent crystallinity content is determined using Differential Scanning calorimetry measurement according to ASTM E 794-85. In another embodiment, the POA's described herein have a percent crystallinity of between 5 and 40%, alternatively between 10 to 30%.

In another embodiment the POA may have a molecular weight distribution (Mw/Mn) of at least 1.5, preferably at least 2, preferably at least 5, preferably at least 10, even alternatively at least 20. In other embodiments the Mw/Mn is 20 or less, 10 or less, even 5 or less. Molecular weight distribution generally depends on the catalysts used and process conditions such as temperature, monomer concentration, catalyst ratio, if multiple catalysts are used, and the presence or absence of hydrogen. Hydrogen may be used at amounts up to 2 weight %, but is preferably used at levels of 50 to 500 ppm.

In another embodiment the POA may be found to have at least two molecular weights fractions present at greater than 2 weight %, preferably greater than 20 weight %, each based upon the weight of the polymer as measured by Gel Permeation Chromatography. The fractions can be identified on the GPC trace by observing two distinct populations of molecular weights. An example would be a GPC trace showing a peak at 20,000 Mw and another peak at 50,000 Mw where the area under the first peak represents more than 2 weight % of the polymer and the area under the second peak represents more than 2 weight % of the polymer.

In another embodiment the POA of this invention may have 20 weight % or more (based upon the weight of the starting polymer) of hexane room temperature soluble fraction, and 70 weight % or less, preferably 50 weight % or less of Soxhlet boiling heptane insolubles, based upon the weight of the polymer. Soxhlet heptane insoluble refers to one of the fractions obtained when a sample is fractionated using successive solvent extraction technique. The fractionations are carried out in two steps: one involves room temperature solvent extraction, the other soxhlet extraction. In the room temperature solvent extraction, about one gram of polymer is dissolved in 50 ml of solvent (e.g., hexane) to isolate the amorphous or very low molecular weight polymer species. The mixture is stirred at room temperature for about 12 hours. The soluble fraction is separated from the insoluble material using filtration under vacuum. The insoluble material is then subjected to a Soxhlet extraction procedure. This involves the separation of polymer fractions based on their solubility in various solvents having boiling points from just above room temperature to 110.degree. C. The insoluble material from the room temperature solvent extraction is first extracted overnight with a solvent such as hexane and heptane (Soxhlet); the extracted material is recovered by evaporating the solvent and weighing the residue. The insoluble sample is then extracted with a solvent having higher boiling temperature such as heptane and after solvent evaporation, it is weighed. The insolubles and the thimble from the final stage are air-dried in a hood to evaporate most of the solvent, then dried in a nitrogen-purged vacuum oven. The amount of insoluble left in the thimble is then calculated, provided the tare weight of the thimble is known.

In another embodiment, the POA's may have a heptane insoluble fraction 70 weight % or less, based upon the weight of the starting polymer, and the heptane insoluble fraction has branching index g' of 0.9 (preferably 0.7) or less as measured at the Mz of the polymer. In a preferred embodiment the composition may also have at least 20 weight % hexane soluble fraction, based upon the weight of the starting polymer. In another embodiment, the POA's may have a heptane insoluble fraction 70 weight % or less, based upon the weight of the starting polymer and a Mz between 20,000 and 5000,000 of the heptane insoluble portion. In a preferred embodiment the composition also has at least 20 weight % hexane soluble fraction, based upon the weight of the starting polymer. In another embodiment the POA's have a hexane soluble portion of at least 20 weight %, based upon the weight of the starting polymer.

In another embodiment the POA comprises propylene and 15 mole % ethylene or less, preferably 10 mole % ethylene or less, more preferably 9 mole % ethylene or less, more preferably 8 mole % ethylene or less, more preferably 7 mole % ethylene or less, more preferably 6 mole % ethylene or less, more preferably 5 mole % ethylene or less, more preferably 4 mole % ethylene or less, more preferably 3 mole % ethylene or less, more preferably 2 mole % ethylene or less, more preferably 1 mole % ethylene or less.

In another embodiment the POA comprises less than 5 mole % of ethylene, preferably less than 4.5 mole % ethylene, preferably less than 4.0 mole % ethylene, alternatively less than 3.5 mole % ethylene, alternatively less than 3.0 mole % ethylene, alternatively less than 2.5 mole % ethylene, alternatively less than 2.0 mole % ethylene, alternatively less than 1.5 mole % ethylene, alternatively less than 1.0 mole % ethylene, alternatively less than 0.5 mole % ethylene, alternatively less than 0.25 mole % ethylene, alternatively 0 mole % ethylene.

For ease of reference the portion of the olefin polymer produced by one of the catalyst may have at least 10% crystallinity may also be referred to as the "semi-crystalline polymer" and the polymer produced by another of the catalyst may have a crystallinity of less than 5%, which may be referred to as the "amorphous polymer."

In another embodiment of this invention the POA may have a characteristic three-zone complex viscosity-temperature pattern, consistent with that shown in FIG. 1. The temperature dependence of complex viscosity was measured using ARES dynamic mechanical spectrometer operating at a frequency of 10 rad/s, with a strain of 20% under a nitrogen atmosphere, and a cooling rate of 10.degree. C./min. The sample was first molten then gradually cooled down to room temperature while monitoring the build-up in complex viscosity. Above the melting point, which is typical of polymer processing temperature, the complex viscosity is relatively low (Zone I) and increases gradually with decreasing temperature. In zone II, a sharp increase in complex viscosity appears as temperature is dropped. The third zone (Zone III) is the high complex viscosity zone, which appears at lower temperatures corresponding to application (end use) temperatures. In Zone III the complex viscosity is high and varies slightly with further decrease in temperature. Such a complex viscosity profile provides, in hot melt adhesive applications, a desirable combination of long opening time at processing temperatures and fast set time at lower temperatures.

In a preferred embodiment, the POA's have less than 1 mol % ethylene, have at least 2 mol % (CH.sub.2).sub.2 units, preferably 4 mol %, preferably 6 mol %, more preferably 8 mol %, more preferably 10 mol %, more preferably 12 mol %, more preferably 15 mol %, more preferably 18 mol %, more preferably 5 mol % as measured by Carbon 13 NMR as described below.

In an another embodiment, the POA's may have between 1 and 10 mol % ethylene, have at least 2+X mol % (CH.sub.2).sub.2 units, preferably 4+X mol %, preferably 6+X mol %, more preferably 8+X mol %, more preferably 10+X mol %, more preferably 12+X mol %, more preferably 15+X mol %, more preferably 18+X mol %, more preferably 20+X mol %, where X is the mole % of ethylene, and the (CH.sub.2).sub.2 units are determined by Carbon 13 NMR as described below.

In a preferred embodiment, the POA's may have less than 1 mol % ethylene, have an amorphous component (i.e., defined to be that portion of the polymer composition that has a crystallinity of less than 5%) which contains at least 3 mol % (CH.sub.2).sub.2 units, preferably 4 mol %, preferably 6 mol %, more preferably 8 mol %, more preferably 10 mol %, more preferably 12 mol %, more preferably 15 mol %, more preferably 18 mol %, more preferably 20 mol % as measured by Carbon 13 NMR as described below.

In an another embodiment, the POA's may have between 1 and 10 mol % ethylene, have an amorphous component (which is defined to be that portion of the polymer composition that has a crystallinity of less than 5%) which contains at least 3+X mol % (CH.sub.2).sub.2 units, preferably 4+X mol %, preferably 6+X mol %, more preferably 8+X mol %, more preferably 10+X mol %, more preferably 12+X mol %, more preferably 15+X mol %, more preferably 18+X mol %, more preferably 20+X mol %, where X is the mole % of ethylene, and the (CH.sub.2).sub.2 units are determined by Carbon 13 NMR as described below.

Functionalized C3-C40 Olefin Polymers (F-POA's)

Any of the polymers described above as POA's may be functionalized and used as F--POA's. Typically, the POA is combined with a free radical initiator and a grafting monomer or other functional group (such as maleic acid or maleic anhydride) and is heated to react the monomer with the POA to form the F-POA.

As stated above, the present invention comprises a functionalized olefin polymer or blend of functionalized olefin polymers, also referred to herein as grafted olefin polymers. By functionalized (or grafted) it is meant that various functional groups are incorporated, grafted, bonded to, and/or physically or chemically attached to the polymer backbone of the POA being functionalized.

In one embodiment, functional groups are grafted onto the POA utilizing radical copolymerization of an functional group, referred to herein as graft copolymerization.

Examples of suitable functional groups include unsaturated carboxylic acids, esters of the unsaturated carboxylic acids, acid anhydrides, di-esters, salts, amides, imides, aromatic vinyl compounds hydrolyzable unsaturated silane compounds and unsaturated halogenated hydrocarbons. Preferred examples of unsaturated carboxylic acids and acid derivatives include, but are not limited to maleic anhydride, citraconic anhydride, 2-methyl maleic anhydride, 2-chloromaleic anhydride, 2,3-dimethylmaleic anhydride, bicyclo[2,2,1]-5-heptene-2,3-dicarboxylic anhydride and 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, crotonic acid, bicyclo(2.2.2)oct-5-ene-2,3-dicarboxylic acid anhydride, 1,2,3,4,5,&g, lo-octahydronaphthalene-2,3-dicarboxylic acid anhydride, 2-oxa-1,3-diketospiro(4.4)non-7-ene, bicyclo(2.2.1)hept-5-ene-2,3-dicarboxylic acid anhydride, maleopimaric acid, tetrahydrophtalic anhydride, norborn-5-ene-2,3-dicarboxylic acid anhydride, nadic anhydride, methyl nadic anhydride, himic anhydride, methyl himic anhydride, and x-methyl-bicyclo(2.2.1)hept-5-ene-2,3-dicarboxylic acid anhydride (XMNA).

Examples of the esters of the unsaturated carboxylic acids include methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate and butyl methacrylate.

Hydrolyzable unsaturated silane compounds useful as functional groups herein may include radical polymerizable unsaturated group and an alkoxysilyl group or a silyl group in its molecule, such that the compound has a hydrolyzable silyl group bonded to a vinyl group and/or a hydrolyzable silyl group bonded to the vinyl group via an alkylene group, and/or a compound having a hydrolyzable silyl group bonded to an ester or an amide of acrylic acid, methacrylic acid or the like. Examples thereof include vinyltrichlorosilane, vinyltris(beta-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane monovinylsilane and monoallylsilane.

Examples of unsaturated halogenated hydrocarbons useful as functional groups herein include vinyl chloride and vinylidene chloride.

In a preferred embodiment, the POA is grafted with maleic anhydride (MA), to produce olefin grafted maleic anhydride (POA-g-MA), wherein the maleic anhydride is bonded to the polymer chain of the polymeric composition.

Preferable examples of the radical initiator used in the graft copolymerization include organic peroxides such as benzoyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, t-butylperoxyisopropyl carbonate, di-ti-butyl perphthalate, 2,5-dimethyl-2,5-di(t-butylperoxy)hexene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexene-3, di-t-butyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, dilauryl peroxide and dicumyl peroxide.

The F-POA of the present invention may thus be obtained by heating the POA(s) and the functional group(s) in the presence of the radical initiator at, near, or above a decomposition temperature of the radical initiator.

In some embodiments, no particular restriction need be put on the amount of the functional group to be used, accordingly, conventional conditions for functionalizing, for example, an isotactic polypropylene, can be utilized with the POA's of this invention. Since in some cases the efficiency of the copolymerization is relatively high, the amount of the functional group may be small. In an embodiment, the amount of the functional group to be incorporated into the POA is preferably from about 0.001 to 50 wt % functional group with respect to the total amount of olefin polymer present, preferably from 0.005 to 40 weight %, preferably from 0.01 to 35 weight %, preferably from about 0.05 to about 30 weight %, more preferably from about 0.1 to about 25 weight %, preferably from about 0.5 to about 20 weight %, preferably from about 1.0 to about 15 weight %, preferably from about 1.5 to 10 weight %, preferably from about 2 to 5 weight %, preferably from about 2 to about 4 weight %. In a preferred embodiment, the amount of the maleic acid and/or maleic anhydride, preferably maleic anhydride, to be incorporated into the POA is preferably from about 0.001 to about 50 wt %, based upon the weight of the POA, preferably from 0.005 to 40 weight %, preferably from 0.01 to 35 weight %, preferably from about 0.05 to about 30 weight %, more preferably from about 0.1 to about 25 weight %, preferably from about 0.5 to about 20 weight %, preferably from about 1.0 to about 15 weight %, preferably from about 1.5 to 10 weight %, preferably from about 2 to 5 weight %, preferably from about 2 to about 4 weight %.

The description continues in the full USPTO document.